This invention relates to a mirror assembly attachment for the distal end of a borescope insertion tube, and more particularly to a motorized rotatable mirror for providing a side looking capability in a standard video borescope.
In many industrial applications where borescopes are used, they have to be inserted a considerable distance into inaccessible cavities for viewing the interior thereof. In long, narrow cavities, and particularly in pipes, it is sometimes difficult to distinguish points of interest on the walls thereof looking straight ahead through the distal end of the borescope insertion tube.
Accordingly, for some time it has been a common practice to provide angled mirrors for allowing viewing at an angle .to the axis of the insertion tube of the borescope, including fixed angular mirrors at the end of a standard borescope and various rotated mirrors, all of which to a degree have allowed viewing of the interior surface walls of the enclosure adjacent the tip of the insertion tube. An angled mirror rotating about the axis of the insertion tube produces a so-called side viewing capability for looking at the walls of a pipe, for instance, as the insertion tube is traversed through the pipe. Rotatable mirrors of this type have been used to reflect the source of light in the distal end of the insertion tube onto the wall of the tube, as the mirror rotates and to pick up the reflected video image so as to scan the entire inside circumference of the pipe as the insertion tube is moved through the pipe.
Since in some installations the borescope insertion tube can have a length of ten to fifty feet, it is important that this adaptor, when mounted on the distal end of a borescope insertion tube be securely fixed thereto so it cannot be accidentally dislodged or disengaged and lost in the interior of a narrow elongated cavity such as a steam pipe.
Various types of rotatable motorized mirrors have been available in the art, and have usually included a motorized assembly with battery and rotating mirror which is in some fashion bolted onto an adaptor ring at the distal end of the insertion tube. Various methods have been used to lock the mounting bolts and pins in place, such as glues or cements, set-screws, double nuts and the like. Not only have these locking means been impractical in use, none are one hundred percent fail-safe, and if one of a three pin mount starts to come loose, the others can also come loose and eventually the powered mirror attachment can be lost.
The present invention provides a self contained motorized mirror assembly that may be quickly and easily mounted on the distal end of an insertion tube of a borescope for changing the field of view of a borescope from straight ahead to side looking, together with a fail-safe mounting preventing accidental disengagement.